I. Field of the Invention
The present invention relates generally to portable electronic devices that include a wireless telephone. More particularly, the present invention relates to a method for reducing power consumption in an integrated electronic device that includes a personal data assistant (PDA) that has been integrated in a common housing with a wireless telephone.
II. Description of the Related Art
Personal data assistants (or PDAs) are well known in the art. Among other things, these devices allow users to run many applications such as personal scheduling programs, address books, games, and notepad programs, on a computer that is sized to fit in a user""s hand. These devices also may include open operating platforms that allow users to program or configure the PDAs themselves.
Wireless telephones are also well known in the art. Such devices typically operate in the cellular or PCS bands, and use technologies such, e.g., code division multiple access or time division multiple access for communication between the wireless telephone and a base station. Some wireless telephones also include pagers that are integrated within the telephone unit. In these units, text messages and other messages such as missed call indication messages may be received in the telephone""s pager from a base station and displayed to the user on the telephone display.
In order to conserve battery power, some wireless telephones function in a xe2x80x9cstandbyxe2x80x9d mode when active voice traffic is not being transmitted between the wireless telephone and a base station. During the standby mode, a receiver in the wireless telephone monitors a channel, such as for example a paging channel, that is used to signal an incoming call to the wireless telephone. Upon receipt of an incoming call (or initiation of an outgoing call by the user), the wireless telephone exits the standby mode and activates the features necessary to support voice traffic between the telephone and a base station. Significantly, during the standby mode the wireless telephone still consumes battery power (which may be used among other things to monitor a paging channel), although power is used more slowly in the standby mode than when active voice communications are being supported on the wireless telephone.
Currently, PDAs and wireless telephones are being provided to users as a single integrated unit. In these products, a PDA and a wireless telephone are disposed in a single housing and use a common display (e.g., LCD display) for communication with the user. In addition, in such units the wireless telephone and the PDA are configured such that a user may program the wireless telephone using the open operating platform of the PDA. In these units, the PDA and the wireless telephone are typically configured to allow data, e.g., fax or data information, to be transferred between the PDA and the wireless telephone. Current products that include both a PDA and a wireless telephone as an integrated unit include the PDQ(trademark)800 and PDQ(trademark)1900 units sold by Qualcomm, Inc.
One problem with existing units that include a combination of a PDA and a wireless telephone is the conservation of battery life. Given that a single battery is typically used to power both the PDA and the wireless telephone, the power demands on the battery can be significant. It is an object of the present invention to provide a system for conserving battery power in such systems, thereby extending the battery life of the units and minimizing the need for recharging of batteries used to power such units.
The present invention is directed to a system and method for reducing power consumed by an integrated electronic device. The device includes a personal data assistant (PDA) unit and a wireless telephone integrated in a common housing. A common display on the housing is used for displaying messages from both the PDA and the wireless telephone to a user. A controller, coupled to the wireless telephone, places the wireless telephone in a power-off state after expiration of a predetermined period of time following cessation of voice traffic activity on the wireless telephone. The controller switches the wireless telephone from the power-off state to a power-on state if, during operation in the power-off state, a user begins an attempt to place an outgoing call with the wireless telephone. The wireless telephone is unable to receive an incoming call when the wireless telephone is in the power-off state. However, the PDA is operable to receive information from the user through the display and display information to the user on the display when the wireless telephone is in the power-off state.
In accordance with a further aspect, the wireless telephone includes a pager that is unable to receive incoming pages when the wireless telephone is in the power-off state. In this embodiment, upon transition from a previous power-off state to a current power-on state, information representative of pages sent to the wireless telephone between cessation of a previous power-on state and initiation of the current power-on state are provided to the user. In a particularly preferred embodiment, the predetermined period of time used for initiation of the power-off state is user selectable and may be either 30 minutes, 60 minutes and 120 minutes. Alternatively, the user is given the option not to activate the power-off feature on the wireless telephone.
The PDA preferably has its own sleep mode that is invoked independently of the current state of the wireless telephone (e.g., power-off state or power-on state). In one embodiment, the PDA has a sleep mode that is invoked by an operating system associated with the PDA after a predetermined period of time following cessation of activity on the PDA. The predetermined period of time used to invoke the sleep mode is preferably user selectable and, in one embodiment, may be either 1, 2, 3, 5 or 15 minutes. Alternatively, the user is given the option not to activate the sleep feature on the PDA.